问在试图升级或安装时出错:新别名:警告: valid_hostname:不正确的分隔符:prabid膝上型计算机。

EN

Postfix (main.cf) configuration was not changed.  If you need to make changes, 
edit /etc/postfix/main.cf (and others) as needed.  To view Postfix 
configuration values, see postconf(1).

After modifying main.cf, be sure to run 'service postfix reload'.

Running newaliases
newaliases: warning: valid_hostname: misplaced delimiter: prabid-HCL-ME-Laptop..name
newaliases: fatal: file /etc/postfix/main.cf: parameter myhostname: bad parameter value: prabid-HCL-ME-Laptop..name
dpkg: error processing package postfix (--configure):
 subprocess installed post-installation script returned error exit status 75
dpkg: dependency problems prevent configuration of mailutils:
 mailutils depends on default-mta | mail-transport-agent; however:
  Package default-mta is not installed.
  Package postfix which provides default-mta is not configured yet.
  Package mail-transport-agent is not installed.
  Package postfix which provides mail-transport-agent is not configured yet.

dpkg: error processing package mailutils (--configure):
 dependency problems - leaving unconfigured
Processing triggers for libc-bin (2.26-0ubuntu2) ...
No apport report written because the error message indicates it's a follow-up error from a previous failure.
                            Errors were encountered while processing:
 postfix
 mailutils
E: Sub-process /usr/bin/dpkg returned an error code (1)